Tuesday, March 25, 2014

Review: Lost Lands for iPhone and iPad

Lost Lands (also free) by Ryan Ding is a seriously challenging maze puzzle that suffered a bit from feature creep but is guaranteed to require all your attention.

The game is entirely based on a single, clever mechanic: L-shaped doors which can only be pushed. This is the same concept as Open Doors and Open Doors 2, two Flash games by Ozzie Mercado (thanks to Keith Harrison for pointing them out to me), but plays quite differently because of the puzzle layout.

Let's see what the doors look like. Here is the first puzzle:

You always start in the top left corner, and need to reach the bottom right (highlighted by a colored gem). In this puzzle, there are just four doors and it's pretty simple. You can just walk all the way to the right, then to the bottom. While passing through the door in the top row, you will push it, so it will rotate clockwise, ending in this position:

Note how every door can be in only one of two positions, because on one side there's a wall, and on the other side there's the doorpost. Understanding how the doors move is by far the hardest thing during the first few levels because, until you learn to distinguish the visual cues, it often looks like you can push a door in a certain direction but you can't.

The fundamental thing to discover is that there are two ways to push a door, which are completely different and have profound effects on solving the puzzles.
The first way is the one seen above, where you push the door from the inside. This move is reversible: you can just walk back through the door, and both you and the door will return to your previous positions.

Soon enough, however, the first kind of move is no longer enough to solve the puzzles. Let's look at another one, and pay attention to the door in the top row:

From this position, you can still walk all the way to the right. In doing so, however, you will push the door from the outside, ending in this position:

Note how this move isn't reversible: now you can walk back left, but the door will not return to its previous position. In a sense, you changed some kind of "parity". You could walk around the top right corner and push the door from the inside, which would return the door to its previous position, but then it would be you that would be on the wrong side of the door.
Pushing doors from the outside, it's actually possible to get stuck into an unwinnable state; luckily, the game kindly informs you when that happens, so you can undo your mistake.

The free version has 168 puzzles in 3 difficulty levels, while the pro version has 480 puzzles in 4 difficulty levels. Interestingly, all the puzzles are played on the same 4x4 grid, with the only thing that changes being the number and position of the doors. The hardest puzzles have 8 doors and look like this:

I found that the best way to solve the puzzles is working backwards from the goal. For example in the puzzle above it's clear that you cannot move the door in the bottom row, because it can only be pushed from the inside, and to do that you would have already reached the gem. Therefore you need to turn the door in the right column, which can only be done by pushing it from the inside: but after doing that, you will be on the wrong side of the door, so you will need to go back to the other side from a different route. Pushing doors from the outside is often the key to prepare an "escape route" to be used after turning some other door. Of course, the harder the puzzles, the more moves you will have to plan in advance.

To move, you simply tap a corner on the same row or column of your man to make him walk. This makes sense because your path can be very convoluted and pass through the same intersection multiple times, so drawing a path wouldn't have worked that well. Your man walk a bit slowly, but you can queue up all the commands needed and then just watch the solution undolf; no need to wait for a move to complete before doing the next.

My main criticism to the game is that it feels overcomplicated. The graphics, while nice, probably make it difficult to clearly understand the mechanics, and the user interface has a bit too many buttons and options, especially in the screen shown after solving a puzzle.

This is certainly not a game for casual players, because understanding its mechanics and taking advantage of them requires discipline. If you feel up to the task (and if you're reading this blog, you should), definitely take a look at it.